Response Analysis Of Large Storage Tank Under Earthquake

Elevated liquid storage tanks are generally applied in petroleum,chemical and other related industries,and they are an important part of industrial facilities.Nowadays,with the continuous development of related industries,the demand for liquid storage tanks is increasing,and there has been an inevitable trend for large-scale liquid storage tanks.The value of liquid storage tanks to society is far greater than its economic value,because the disaster will be extremely serious when the tank is destroyed by earthquake,and often accompanied by secondary disasters,causing huge losses to production and national economy,leading to terrible consequences and long-term environmental damage.Therefore,it is necessary to study the seismic behavior of large-scale storage tanks.At present,most of the theoretical basis for the response analysis of liquid storage tanks in specifications are Housner mechanical model and Haroun-Housner mechanical model.However,the two added mass models are proposed based on one-dimensional earthquake,and it is difficult to simulate the real dynamic response of liquid storage tanks under earthquakes.Although the fluid-structure interaction method is very accurate in theory,it is difficult to achieve in reality.This paper conducts the following research for solving this problem :(1)The structure of large-scale elevated liquid storage tank in practical engineering is simplified and modeled.Two added mass models are used for time history analysis under one-dimensional excitation,on which basis,the use method of extending the additional mass method to two-dimensional is proposed.The dynamic response is obtained by finite element analysis.By comparing the results of base shear,base bending moment,displacement and acceleration with the standard values,it shows that the results obtained by extending the added mass method to two-dimensional are more accurate.From the perspective of model simplification,the specific application of added mass model is further improved.(2)Considering liquid sloshing,liquid surface movement and other factors,the fluid-structure interaction method is used for modeling.The results of time history analysis under two-dimensional seismic excitation are close to the results of added mass method,which also verifies the correctness of the extension of the additional mass method to two-dimensional use.Under the three-dimensional seismic excitation,the dynamic response of the liquid storage tank increases significantly,which will be greater than some standard values,indicating that the results only considering the horizontal excitation are insufficient.However,the method of fluid-structure interaction takes a long time to calculate and it is not easy to realize.Therefore,the results of dynamic response of liquid storage tank under multi-dimensional earthquake are simulated by multiplying the corresponding amplification coefficient based on the results of additional mass method,and this method is easy to implement and accurate.The structural design is safe and reliable,and it is also the basis for evaluating the feasibility of liquid storage tank design.(3)Time-history analysis is carried out on the liquid storage tanks with large height and diameter and large volume under multi-dimensional seismic excitation.By comparing the responses of tank wall deformation and acceleration under different working conditions,the position where the maximum value occurs is determined,and the position where the liquid storage tanks are easily damaged under multi-dimensional seismic excitation is found out.The failure mode of the whole structure of the liquid storage tank under the limit state is obtained,which also provides theoretical reference and basis for the standard design of this kind of liquid storage tanks.(4)With the continuous emergence of new chemical processes,there have been many liquid storage tanks with high base.This paper conducts relevant research and analysis so as to examine the impact of base height,which can provide engineering advice from the perspective of earthquake resistance for the needs of large-scale liquid storage tank foundations.